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A161903 Convert n into a sequence of binary digits, apply one step of the rule 110 cellular automaton, and interpret the results as a binary integer. 5
0, 3, 6, 7, 12, 15, 14, 13, 24, 27, 30, 31, 28, 31, 26, 25, 48, 51, 54, 55, 60, 63, 62, 61, 56, 59, 62, 63, 52, 55, 50, 49, 96, 99, 102, 103, 108, 111, 110, 109, 120, 123, 126, 127, 124, 127, 122, 121, 112, 115, 118, 119, 124, 127, 126, 125, 104, 107, 110, 111, 100, 103, 98, 97, 192, 195, 198, 199, 204, 207, 206, 205, 216, 219, 222, 223, 220, 223, 218, 217, 240, 243, 246, 247, 252, 255, 254, 253, 248, 251, 254, 255, 244, 247, 242, 241, 224, 227, 230, 231, 236 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

a(a(a(...1))) (n times) gives A006978(n)

LINKS

T. D. Noe, Table of n, a(n) for n = 0..1023

Index entries for sequences related to cellular automata

Eric Weisstein's World of Mathematics, Rule 110

Wikipedia, Rule 110

FORMULA

a(n) = A057889(A269174(A057889(n))). - Antti Karttunen, Jun 02 2018

EXAMPLE

For n=19, the evolution after one step is

0, 1, 0, 0, 1, 1  (n=19)

1, 1, 0, 1, 1, 1  (a(n)=55)

So a(n)=55.

MATHEMATICA

a[n_] :=

FromDigits[

  Drop[Part[CellularAutomaton[110, {IntegerDigits[n, 2], 0}], 1], -1],

   2]; Table[a[n], {n, 0, 100}]

CROSSREFS

Cf. A006978, A070887, A071049, A180001, A186083, A204371.

Cf. also A269160, A269174, A269175.

Sequence in context: A242666 A226228 A269174 * A163617 A189634 A047705

Adjacent sequences:  A161900 A161901 A161902 * A161904 A161905 A161906

KEYWORD

nonn,base

AUTHOR

Ben Branman, Jan 30 2011

STATUS

approved

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Last modified April 19 14:14 EDT 2019. Contains 322280 sequences. (Running on oeis4.)